Hmm, on second thought: A high- or normal-priority task X will preempt any number of low-priority tasks Y at the level of logical cores, but not necessarily at the level of physical cores. I.e. if you have some physical cores which serve just one thread, and other physical cores which serve two threads, then I don't know whether the Windows process scheduler is clever enough to put higher-priority tasks onto the less utilized physical cores.2. Or increase the scheduler priority of the GPU supporter process from low to normal. In the latter case, you can have as many low-priority processes from CPU DC workers as you like, but they will always yield a core (presumably without HT penalty) to the normally prioritized thread as soon as that one becomes runnable.